Search Results (510)

Rosa hybrida is a globally important ornamental species, but its economic and aesthetic value is often compromised by rose black spot disease (Diplocarpon rosae). Effective monitoring and early detection are essential for disease management. This study investigated physiological and biophysical responses to infection in a resistant cultivar (‘Carefree Wonder’) and a susceptible cultivar (‘Red Cap’) using electrical impedance spectroscopy (EIS), biochemical assays, and ultrastructural analysis. Key EIS parameters (r_i, r_e, τ), reducing sugar and free proline content, chitinase and β-1,3-glucanase activities, and chloroplast ultrastructure were monitored. The results showed that ‘Carefree Wonder’ had a higher initial EIS arc magnitude and osmolyte levels than ‘Red Cap’. Following infection, ‘Red Cap’ displayed earlier and more pronounced increases in EIS arc magnitude, while ‘Carefree Wonder’ responded more gradually. Reducing sugar and proline levels increased in both cultivars, with earlier accumulation in the resistant cultivar. Notably, extracellular resistivity (r_e) exhibited strong positive correlations with reducing sugar (R² = 0.479), free proline (R² = 0.399), chitinase (R² = 0.399), and β-1,3-glucanase activities (R² = 0.401). These findings highlight r_e as the most reliable EIS-derived indicator for early, non-destructive detection of rose black spot resistance. This study supports the potential of EIS for rapid disease diagnostics in rose breeding and cultivation. Full article

Surfactants are widely utilized in agriculture as emulsifying, dispersing, anti-foaming, and wetting agents. In these adjuvant roles, the inherent biological activity of the surfactant is secondary to the active ingredients. Here, the hydrophilic non-ionic surface-active tri-block copolymer Pluronic^® F68 is investigated for direct biological activity in wheat. F68 binds to and inserts into lipid membranes, which may benefit crops under abiotic stress. F68’s interactions with Triticum aestivum (var Juniper) seedlings and a seed-borne Bacillus spp. endophyte are presented. At concentrations below 10 g/L, F68-primed wheat seeds exhibited unchanged emergence. Root-applied fluorescein-F68 (fF68) was internalized in root epidermal cells and concentrated in highly mobile endosomes. The potential benefit of F68 in droughted wheat was examined and contrasted with wheat treated with the osmolyte, glycine betaine (GB). Photosystem II activity of droughted plants dropped significantly below non-droughted controls, and no clear benefit of F68 (or GB) during drought or rehydration was observed. However, F68-treated wheat exhibited increased transpiration values (for watered plants only) and enhanced shoot dry mass (for watered and droughted plants), not observed for GB-treated or untreated plants. The release of seed-borne bacterial endophytes into the spermosphere of germinating seeds was not affected by F68 (for F68-primed seeds as well as F68 applied to roots), and the planktonic growth of a purified Bacillus spp. seed endophyte was not reduced by F68 applied below the critical micelle concentration. These studies demonstrated that F68 entered wheat root cells, concentrated in endosomes involved in transport, significantly promoted shoot growth, and showed no adverse effects to plant-associated bacteria. Full article

Salinity stress is a primary abiotic constraint limiting global crop productivity, with progressive soil salinization inducing growth inhibition and physiological dysfunction in plants. Although melatonin (MT) has been extensively documented to enhance stress adaptation, the underlying mechanisms through which it mediates salt tolerance by integrating physiological processes remain unclear. This study investigated the effects of varying MT concentrations on photosynthetic performance, plant water relations, water-use efficiency, and stress-responsive physiological parameters in tomatoes, aiming to identify the key physiological pathways for MT-mediated salt stress mitigation. The results showed that salt stress significantly reduced the leaf relative water content and root hydraulic conductivity, suppressed the photosynthetic rate, and ultimately caused significant reductions in the aboveground and root biomass. MT spraying effectively improved leaf water status and root water uptake capacity, enhancing the photosynthetic rate and water-use efficiency, thereby providing material and energy support for plant growth. Furthermore, MT spraying increased the total antioxidant capacity in leaves and promoted the synthesis of phenolic and flavonoid compounds, thereby reducing oxidative damage. Simultaneously, it stimulated the accumulation of osmolytes to enhance cellular osmotic adjustment capacity and optimized ion uptake to maintain cellular ion homeostasis. Among the tested concentrations, 100 μM MT showed the most significant alleviative effects. This concentration comprehensively enhanced the salt tolerance and growth performance of tomato plants by synergistically optimizing water use, photosynthetic function, antioxidant defense, and ion balance. In conclusion, these findings provide experimental evidence for elucidating the physiological mechanisms underlying MT-mediated salt tolerance in tomatoes and offer theoretical references for the rational application of MT in crop production under saline conditions. Full article

Salinization severely impairs crop growth by inducing oxidative stress and disrupting cellular homeostasis. This study systematically investigates the synergistic effects of salt-tolerant plant-growth-promoting rhizobacteria (ST-PGPR) and foliar silicon fertilizer spraying (FSFS) on antioxidant responses in Pak choi under salt stress. Two-season pot experiments were carried out to evaluate key indicators, including antioxidant enzyme activities (superoxide dismutase: SOD; peroxidase: POD; catalase: CAT), oxidative stress (malondialdehyde: MDA), osmolyte accumulation (proline, soluble protein), and hormones (Jasmonic Acid: JA; Salicylic Acid: SA; Abscisic acid: ABA). The results demonstrate that combining ST-PGPR with FSFS significantly enhances SOD (6.18–2353.85%), POD (3.44–153.29%), and CAT (25.71–319.29%) activities while reducing MDA content (8.12–35.87%). Proline and soluble protein levels increased by 1.56–15.71% and 5.03–188.87%, respectively. Hormonal regulation increased JA, SA, and ABA levels by 1.05–31.81%, 2.09–34.29%, and 3.18–30.09%, respectively. Notably, ST-PGPR treatments at 10⁴ and 10⁶ cfu·mL⁻¹, combined with foliar silicon application, consistently ranked highest in overall antioxidant performance across both seasons based on a principal component analysis. These findings provide novel insights into microbial–mineral interactions for sustainable saline agriculture. Full article

Salinity and heavy metal stress significantly reduce agricultural productivity in arable lands, particularly affecting crops like rice (Oryza sativa L.). This study aimed to evaluate the efficacy of heavy metal-tolerant plant growth-promoting rhizobacteria (HMT-PGPR) in mitigating the harmful effects of salt (NaCl), chromium (Cr), and combined NaCl + Cr stress on rice plants. Two pre-isolated and well-characterized heavy metal-tolerant epiphytic (Ochrobactrum pseudogrignonense strain P14) and endophytic (Arthrobacter woluwensis strain M1R2) PGPR were tested. The LSD test (p ≤ 0.05) was used to assess the statistical significance between treatment means. Stresses caused by NaCl, Cr, and their combination were found to impair plant growth and biomass accumulation through mechanisms, including osmotic stress, oxidative damage, ionic imbalance, reduced photosynthetic pigment, lowered relative water content, and compromised antioxidant defense systems. Conversely, inoculation with HMT-PGPR alleviated these adverse effects by reducing oxidative stress indicators, including malondialdehyde (MDA), hydrogen peroxide (H₂O₂) content and electrolyte leakage (EL) and enhancing plant growth, osmolyte synthesis, and enzymatic antioxidant activity under single- and dual-stress conditions. The application of HMT-PGPR notably restricted Na⁺ and Cr⁶⁺ uptake, with an endophytic A. woluwensis M1R2 demonstrating superior performance in reducing Cr⁶⁺ translocation (38%) and bioaccumulation (42%) in rice under dual stress. The findings suggest that A. woluwensis effectively mitigates combined salinity and chromium stress by maintaining ion homeostasis and improving the plant’s antioxidant defenses. Full article

Betaine, a naturally occurring compound primarily derived from sugar beet by-products, has attracted increasing attention for its multifaceted roles in human and animal nutrition. Acting as both an osmolyte and a methyl group donor, betaine contributes to cellular hydration, methylation balance, antioxidant defense, and metabolic regulation. This review provides a comprehensive overview of betaine’s biological functions and its health-promoting effects across species. In humans, betaine supports hepatic function, cardiovascular health, renal protection, and physical performance, mainly by modulating homocysteine metabolism, lipid profiles, and oxidative stress. In animal production systems, it enhances growth, feed efficiency, reproductive performance, and resilience to heat stress, with species-specific applications in monogastrics, ruminants, aquaculture species, and companion animals. The review also explores the molecular mechanisms underlying betaine’s effects, including epigenetic regulation and mitochondrial function, and presents updated evidence on its biosynthesis, bioavailability, and nutrient interactions. Furthermore, the use of betaine derived from agro-industrial by-products aligns with the principles of the circular economy, promoting the sustainable reuse of valuable compounds within the agri-food chain. Despite promising findings, further research is needed to standardize effective dosages and clarify species-specific responses under different physiological and environmental conditions. Overall, betaine emerges as a promising and sustainable functional ingredient with wide-ranging applications in nutrition and health. Full article

Cold stress adversely impacts tomato (Solanum lycopersicum) production, particularly in temperate regions, by impairing growth, development, and yield. Abscisic acid (ABA), a key phytohormone, plays a central role in mediating tomato’s response to cold stress through a complex crosstalk network with other hormones and signaling molecules. This review examines ABA’s interactions with hormones such as ethylene, jasmonates, auxin, gibberellins, salicylic acid, brassinosteroids, and strigolactones, as well as signaling molecules like hydrogen peroxide, nitric oxide, hydrogen sulfide, and calcium. These interactions regulate various physiological processes, including osmolyte accumulation, membrane stability, and oxidative stress mitigation, and influence the expression of cold-responsive genes, such as CBFs, COR, and LEA. Critical knowledge gaps remain, particularly in understanding ABA’s context-specific interactions with other hormones and the integration of calcium signaling with ABA pathways under cold stress. By synthesizing current research, this review enhances our understanding of tomato’s cold stress response and provides insights for genetically improving cold tolerance, supporting sustainable tomato production amid climate challenges. Full article

To date, the nitrogen metabolism pathways and salt-tolerance mechanisms of halophilic denitrifying bacteria have not been fully studied, and full-scale engineering trials with saline fly ash-washing wastewater have not been reported. In this study, we isolated and screened a halophilic denitrifying bacterium (Marinobacter sp.), GH-1, analyzed its nitrogen metabolism pathways and salt-tolerance mechanisms using whole-genome data, and explored its nitrogen removal characteristics under both aerobic and anaerobic conditions at different salinity levels. GH-1 was then applied in a full-scale engineering project to treat saline fly ash-washing leachate. The main results were as follows: (1) Based on the integration of whole-genome data, it is preliminarily hypothesized that the strain possesses complete nitrogen metabolism pathways, including denitrification, a dissimilatory nitrate reduction to ammonium (DNRA), and ammonium assimilation, as well as the following three synergistic strategies through which to counter hyperosmotic stress: inorganic ion homeostasis, organic osmolyte accumulation, and structural adaptations. (2) The strain demonstrated effective nitrogen removal under aerobic, anaerobic, and saline conditions (3–9%). (3) When applied in a full-scale engineering system treating saline fly ash-washing wastewater, it improved nitrate nitrogen (NO₃⁻-N), total nitrogen (TN), and chemical oxygen demand (COD) removal efficiencies by 31.92%, 25.19%, and 31.8%, respectively. The proportion of Marinobacter sp. increased from 0.73% to 3.41% (aerobic stage) and 2.86% (anoxic stage). Overall, halophilic denitrifying bacterium GH-1 can significantly enhance the nitrogen removal efficiency of saline wastewater systems, providing crucial guidance for biological nitrogen removal treatment. Full article

Background/Objectives: Drought stress is a significant environmental challenge that affects plant growth and productivity. Methods: In this study, an underutilized and better drought stress tolerance genotype of Cucumis melo var. melo, i.e., AHK-200, was investigated for drought tolerance potential, with special emphasis on various morphological, physiological, biochemical, and molecular parameters. Results: Our findings show that AHK-200 demonstrates superior drought tolerance with an enhanced root length, better water retention capacity, and stable cell membrane integrity under water deficit conditions. Physiologically, AHK-200 exhibited minimal reduction in relative water content (RWC) and photosynthetic efficiency (PN), along with increased stomatal conductance (gs) and chlorophyll content and reduced photoinhibition under drought stress. Biochemically, AHK-200 showed higher antioxidant enzyme activity (APX, CAT, SOD, GR, POD) and osmolyte accumulation (proline), which are critical for mitigating oxidative stress. At the molecular level, drought-related genes such as DREB2C, DREB2D, and RD22 were upregulated, supporting AHK-200 resilience to drought stress. Additionally, AHK-200 displayed elevated mineral concentrations, including Na, K, Ca, and Fe, which are essential for cellular homeostasis and stress adaptation. Conclusions: Overall, our study provides a comprehensive understanding of the drought tolerance mechanisms in AHK-200, highlighting its potential for use in breeding drought-tolerant genotypes in cucurbits and related crops. This research could guide future efforts in gene manipulation and transgenic development aimed at enhancing drought resistance and yield potential in crop plants. Furthermore, DREB2C, DREB2D, and RD22 transcription factors regulate many pathways related to stress; the overexpression of these genes may open a new avenue in melon improvement against drought stress. Full article

Soil contamination with arsenic (As) is becoming a serious concern for living organisms. Arsenic is a nonessential metalloid for plants, humans, and other living organisms. Biochar (BC) is a very effective amendment to remediate polluted soils and it received great attention owing to its appreciable results. Arsenic toxicity negatively affects plant morph-physiological and biochemical functioning and upsurges the generation of reactive oxygen species (ROS), which negatively affect cellular structures. Arsenic toxicity also reduces seed germination and impedes plant growth by decreasing nutrient uptake, causing oxidative damage and disrupting the photosynthetic efficiency. Plants use different strategies like antioxidant defense and increased osmolyte synthesis to counteract As toxicity; nevertheless, this is not enough to counter the toxic impacts of As. Thus, applying BC has shown tremendous potential to counteract the As toxicity. Biochar application to As-polluted soils improves water uptake, maintains membrane stability and nutrient homeostasis, and increases osmolyte synthesis, gene expression, and antioxidant activities, leading to better plant performance. Additionally, BC modulates soil pH, increases nutrient availability, causes As immobilization, decreases its uptake and accumulation in plant tissues, and ensures safer production. The present review describes the sources, toxic impacts of As, and ways to lower As in the environment to decrease its toxic impacts on humans, the ecosystem, and the food chain. It concentrates on different mechanisms mediated by BC to alleviate As toxicity and remediate As-polluted soils and different research gaps that must be fulfilled in the future. Therefore, the current review will help to develop innovative strategies to minimize As uptake and accumulation and remediate As-polluted soils to reduce their impacts on humans and the environment. Full article

This review examines the impact of heat stress (HS) on carcass traits, meat quality, and nutritional composition in monogastric animals, specifically poultry and swine, and evaluates targeted nutritional strategies for mitigation. With rising global temperatures and intensified heat waves, HS has emerged as a key threat to animal welfare, production efficiency, and meat quality. Physiological disturbances induced by HS, including oxidative stress, protein denaturation, mitochondrial dysfunction, and hormonal imbalances, contribute to reduced carcass yield, muscle degradation, and inferior sensory attributes such as tenderness, juiciness, and flavour. HS also diminishes the nutritional value of meat by depleting essential amino acids, polyunsaturated fatty acids, and antioxidant micronutrients. This review highlights nutritional interventions, including antioxidant supplementation (e.g., vitamin E, selenium, polyphenols), osmolytes (e.g., betaine, taurine), probiotics, prebiotics, and optimised energy-to-protein ratios, as promising tools to enhance thermotolerance and meat quality. Emerging feed additives such as phytochemicals also show potential for protecting muscle integrity and improving oxidative stability. Given species-specific responses and production system variability, integrating these dietary approaches with stage-specific management is essential for resilience under climate stress. Future research should focus on the precision nutrition, biomarker identification, and validation of synergistic nutritional strategies that safeguard performance and meat quality in monogastric production systems. Full article

The agricultural sector plays one of the pivotal roles in fulfilling the objectives set forth by the EU Green Deal. However, the extensive use of synthetic fertilizers has contributed to nutrient over-enrichment in aquatic ecosystems, promoting eutrophication due to excess nitrogen inputs from fertilizers. This phenomenon is a key driver of rapid and excessive algal blooms in rivers, lakes, and seas. In this study, three globally cultivated crop species—oilseed rape (Brassica napus L.), common wheat (Triticum aestivum L.), and pea (Pisum sativum L.)—were selected for experimental analysis, including the assessment of biochemical parameters such as proline content, lipid peroxidation levels, hydrogen peroxide production, total phenol content, and antioxidant activity, which were evaluated to determine the potential of phytoplankton biomass as a substitute for synthetic fertilizers. Various quantities of lyophilized phytoplankton biomass, collected from the Curonian Lagoon, a biologically productive and ecologically sensitive brackish water body in the southeastern Baltic region, were incorporated into the growth substrates of the studied plants. The findings indicate that utilizing excess phytoplankton biomass can serve not only as a plant growth biostimulant but also as a sustainable alternative to synthetic fertilizers, thereby contributing to improved water quality and more environmentally responsible agricultural practices. Full article

Rising global temperatures driven by climate change have markedly increased the incidence of heat stress (HS) in monogastric livestock, posing critical challenges to animal welfare, health and productivity. This review provides a comprehensive analysis of the physiological and metabolic responses to HS in species such as poultry and swine. It details both the rapid thermoregulatory adaptations, including increased respiratory rate and peripheral vasodilation, and the sustained activation of the hypothalamic-pituitary-adrenal axis that elevates stress hormone levels. Chronic heat exposure disrupts immune function, induces oxidative stress via excessive reactive oxygen species production, and shifts metabolic balance from anabolic to catabolic processes, thereby impairing muscle development and compromising carcass composition. In response, a range of nutritional and management interventions, including antioxidant and osmolyte supplementation, dietary adjustments, enhanced housing designs, and genetic selection for heat tolerance, have been explored to mitigate these adverse effects. By integrating these multidisciplinary strategies, producers can improve animal welfare, sustain productivity, and preserve meat quality under escalating thermal challenges. The review further emphasizes the need for advanced monitoring technologies and precision livestock farming approaches to develop resilient, adaptive production systems in an era of climate uncertainty. Full article

Trimethylamine N-oxide (TMAO) is an endogenous osmolyte produced by enzymatic reactions starting in the human gut, where microbiota release trimethylamine (TMA) from foods, and ending in the liver, where TMA is oxidized to TMAO by flavin-containing monooxygenase 3 (FMO3). While physiological concentrations of TMAO help proteins preserve their folding, high levels of this metabolite are harmful and promote oxidative stress, inflammation, and atherosclerosis. In humans, elevated levels of circulating TMAO predispose individuals to cardiovascular diseases and chronic kidney disease and increase mortality risk, especially in the elderly. How TMAO exerts its negative effects has been only partially elucidated. In hypertensive rats, the eNOS substrate L-arginine and Taurisolo^®, a nutraceutical endowed with TMAO-reducing activity, act synergistically to reduce arterial blood pressure. Here, we investigate the molecular mechanisms underpinning this synergism and prove that TMAO, the target of Taurisolo^®, acts as direct inhibitor of endothelial nitric oxide synthase (eNOS) and competes with L-arginine at its catalytic site, ultimately inhibiting NO production and acetylcholine (Ach)-induced relaxation in murine aortas. Full article

Lippia alba (Mill.) N.E.Br. ex Britton and P. Wilson is a native plant of Colombia, widespread throughout Central and South America, used for thousands of years by pre-Columbian populations, who already knew the many beneficial properties of this species (e.g., antifungal, antibacterial, antiviral and anti-inflammatory activities). The essential oil of L. alba is rich in phytochemicals with antioxidant activity that could be very useful both for pharmacology and biotechnology application, such as the protection of horticultural crops sensitive to salinity. To enhance salt tolerance, seed-priming treatment with the essential oil of L. alba was performed. We evaluated the effect of this biostimulant on the response to salt stress in a sensitive bean species, Phaseolus acutifolius L. (cv Blue Tepary), native to Mexico, and used by pre-Columbians as well as nowadays. Bean seeds were primed in a solution of 0.5 mL/L of essential oil of L. alba, germinated and after 2 weeks of acclimation, the seedlings were subjected to salt stress, by watering with 40 mM and 80 mM NaCl solutions. Four weeks later, many biochemical parameters were evaluated in order to test the effects of the treatments on plant fitness. Primed seeds showed an increase in salt tolerance during germination, as well as primed plants revealing a higher water uptake, increased chlorophylls, proline content and salt tolerance index. The treatments also improved the Ca²⁺ concentration in the shoots of stressed primed plants, more quickly activating enzymatic responses to salinity—in particular superoxide dismutase, polyphenol oxidase, catalase, peroxidase and ascorbate peroxidase—compared to unprimed stressed plants. In conclusion, L. alba was found to be a strong elicitor of responses against osmotic and oxidative stress, as induced by salinity, suggesting the possibility of its future utilization in agriculture. Full article